Shape memory behavior of a partially zincneutralized, poly(ethylene-co-methacrylic acid) ionomer was investigated. The ionomer was a semicrystalline ionomer with a broad melting transition in the range 60−100 °C. Physical crosslinks in the ionomer due to an ionic nanodomain structure provided a "permanent" crosslinked network, while polyethylene crystallinity provided a temporary network. The broad melting transition allowed one to tune the dual-shape memory behavior by choosing a switching temperature, T c , anywhere within the melting transition. Similarly, multiple-shape memory behavior was achieved by choosing two or more switching temperatures within the melting transition, though the effectiveness of fixing (F) depended on how much material was melted and recrystallized to support the specific temporary shape. Crosslinking improved the recovery efficiency (R), and the crosslinked ionomer exhibited nearly ideal shape memory behavior in the dual-shape memory cycle.

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The use of elastomers in oil industry extends over a broad range of applications including seals, packing elements, reactive rubber elements, stators, and pads. These applications require a variety of property requirements that may differ for dynamic and static applications or include a need for stimuli-responsive capabilities in certain tools. This research details the effect of nanofillers on elastomer properties for oil and gas components. The effects include enhancement of mechanical properties, wear resistance, thermal conductivity and heat expansion properties. In addition, effects of nanofillers on rapid gas decompression (RGD) resistance, chemical resistance to downhole fluids, and resistance to chemical aging at downhole temperatures were investigated. Advanced rubber nanocomposites formulations, based on Hydrogenated Nitrile Butadiene Rubber (HNBR) elastomers, were designed internally. Their properties were assessed using methods and techniques to qualify elastomers for downhole applications. Mechanical properties of elastomers were evaluated at room temperature and at 325° F, which is a maximum application temperature for HNBR elastomers. RGD testing was conducted according to ISO standards. Results indicated that it is possible to control mechanical properties of elastomers with nanotechnology, including improving the abrasion resistance of the elastomers by more than 100% in dynamic, wear-intensive applications, when compared to commercial compounds typically used in the oil industry. Thermal conductivity was improved by up to 40%, while heat expansion decreased by 30%, providing more versatility for seal design in dynamic applications which are prone to localized heating. In addition, RGD resistance in nanocomposites was examined and compared it to control samples. The industrial scale feasibility for nano-enhanced elastomers was demonstrated by a scale-up study.

Materials with enhanced properties permitting operations under increasingly harsh conditions such as high pressure, high temperature, high salinity, and sour environments are in critical need for the oil industry. The recent progress in composite materials has been facilitated by engineered nanoparticles dispersed or in situ generated in different matrix media. The cases representing examples considered in this paper include elastomers filled with carbon nanotubes, both in as-received and surface-functionalized compositions; metal matrix composites with added diamond nanoparticles; and scintillating glass ceramic nanocomposites. New nanocomposite materials prepared, characterized, and tested demonstrate enhanced mechanical and optical properties, as well as improved thermal and chemical stability, in line with requirements for demanding oilfield applications.

This paper describes the use of nanotechnology for transforming conventional composites that are commonly used in oilfield applications into smart materials with the ability to transmit pertinent data from downhole operations and activities. The oil and gas industry already uses stimuli-responsive materials for numerous technologies including swellable elastomers in reactive packers and in heat/ fluid-activated expandable screens. This research details the digitization of stimuli-responsive materials through the integration of a network of conductive nanomaterials into an elastomer matrix. As a result, sensors with a wide array of detection capabilities become possible. For instance, it is possible to monitor the degree and rate of a material’s expansion downhole – such as in packers or sand screens. Such information can be used to detect tool deployment status, degradation, or even chemical detection. In addition, the conductivity data resulting from nano-enabled smart composites described here can be used to detect the presence of oil, water, or specific chemicals.